INTRODUCTIONAlthough joint aspiration with synovial fluid analysis is useful in the diagnosis of crystal or septic arthritis, the frequency with which it provides a diagnosis or aids subsequent management of patients with arthritis has not been well quantified. We therefore evaluated the usefulness of joint aspiration in the diagnosis and management of patients with arthritis in a hospital-based rheumatology service.

MATERIALS AND METHODSWe reviewed records of all patients with joint aspiration performed by an inpatient rheumatology service in a tertiary referral hospital from November 2003 to December 2004. Data were extracted on the frequency with which joint aspiration provided a diagnosis or aided management.

RESULTSAmong 76 patients [mean +/- standard deviation (SD), 60.9 +/- 15.9 years; 41 males, 35 females, Chinese (50), Malay (20), Indian (4) and others (2)] with 86 joint aspirations, a definitive diagnosis was obtained in 44% of procedures which showed gout (n = 28), septic arthritis (n = 8) or pseudogout (n = 2). In another 47% of procedures, joint aspiration aided diagnosis by allowing categorisation of synovial fluid as inflammatory (n = 25), non-inflammatory (n = 16) or blood-stained (n = 2). Joint(s) aspirated were knees (71%), ankles (15%), elbows (8%), shoulders (2%) and wrists, metacarpo-phalangeal and metatarso-phalageal (approximately 1% each).

CONCLUSIONJoint aspiration provides a definitive diagnosis or information that aids diagnosis in a significant number of patients in a hospital-based rheumatology service.